The genesis of epigenetic alteration and its relationship with uranium mineralization in the Nalinggou uranium deposit, Ordos Basin

The Nalinggou sandstone-hosted uranium deposit is a large-sized paleo-interlayer oxidation zone sandstone type uranium deposit. According to the study of the relationship between alteration and uranium mineralization, a new classification method for epigenetic alteration in paleo-interlayer oxidation zone sandstone type uranium deposits was established. There are three categories, i.e., ore control alteration, mineralization alteration, and ore-protecting alteration. The spatial distribution of epigenetic alteration was analyzed vertically and horizontally. On cross sections, from the bottom to top, there exists a vertical alteration sequence of ore-protecting alternation, mineralization alteration, and ore control alteration. This paper also discussed distribution characteristics of the thickness of oxidized sandstone, the percentage of oxidized sandstone, the bottom depth of oxidized sandstone, and the elevation of oxidized sandstone bottom.